Calder, C.S.T. and Edwards, A.J.H. 1938. Excavations of Three Neolithic Chambered Cairns – One with an Upper and a Lower Chamber – in the Islands of Eday and the Calf of Eday in Orkney: Including Report on the Pottery. Proceedings of the Society of Antiquaries of Scotland. 72, (Nov. 1938), 193–213. DOI:https://doi.org/10.9750/PSAS.072.193.213.